1. Field of the Invention
The invention relates to an ink transfer device which can be clamped on a rubber covered cylinder in a printing press, including a rubber blanket, a carrier element fixed to the rubber blanket, and a pair of fixing elements for clamping the blanket on the cylinder, the fixing elements being positioned on the carrier adjacent to respective ends of the blanket.
2. Description of the Related Art
In the printing units of a printing press, with the aid of what are known as inking units, printing ink is transferred as a function of a subject onto a printing forme positioned on a forme cylinder of the respective printing unit. With the aid of an ink transfer device, the printing ink applied to the printing forme is transferred to a printing material to be printed. Transfer devices known from the prior art are based either on what are known as rubber blankets or on what are known as rubber sleeves.
Rubber sleeves are formed in the manner of sleeves and, in order to position the same on a rubber-covered cylinder, are pushed onto the rubber-covered cylinder in the axial direction. Rubber sleeves have the advantage that non-ink-carrying gaps or channels in the region of the ink transfer device are avoided. Rubber sleeves of this type therefore benefit a quiet rolling behavior of printing cylinders on one another and in this way minimize cylinder oscillations. Ink transfer devices based on rubber sleeves require a great deal of mechanical effort, however, and are therefore relatively expensive.
By contrast, rubber blankets must be clamped on the rubber-covered cylinder in what are known as clamping channels. The relatively flexible rubber blankets are accommodated on a preferably metallic carrier element, end sections of the carrier element being bent over in order to form fixing elements, which are used for clamping the rubber blanket on the rubber-covered cylinder. According to the prior art, the fixing elements are a constituent part of the carrier element.
During the clamping, non-ink-transferring gaps or channels are formed in between what is known as a leading end and what is known as a trailing end of the rubber blanket, and have a detrimental influence on the rolling behavior of printing cylinders and thus, in particular in the case of relatively slim cylinders and in the case of relatively high rotational speeds of the same, can cause cylinder oscillations. Ink transfer devices based on rubber blankets are certainly less expensive but the print quality that can be realized is restricted with regard to oscillation stripes as compared with ink transfer devices based on rubber sleeves.